rs727504336

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

This summary comes from the ClinGen Evidence Repository: The NM_000257.3(MYH7):c.1477_1478delAT (p.Met493Valfs) variant has been identified in 1 individual with features of both HCM and DCM (Zimmerman 2010 PMID:20474083; Walsh 2017 PMID:27532257, LMM pers. comm.) however, this is insufficient to apply the PS4 criterion. This variant was absent from large population studies (PM2; http:// gnomad.broadinstitute.org, v.2.1.1). This variant is predicted to cause a frameshift leading to a truncated or absent protein. The contribution of loss of function (LOF) variants in MYH7 to autosomal dominant inherited cardiomyopathy is incompletely understood therefore PVS1 was not applied. In summary, due to insufficient evidence, this variant meets criteria to be classified as uncertain significance for cardiomyopathy in an autosomal dominant manner. MYH7-specific ACMG/AMP criteria applied (Kelly 2018 PMID:29300372): PM2. LINK:https://erepo.genome.network/evrepo/ui/classification/CA010796/MONDO:0004994/002

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000041 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

MYH7
NM_000257.4 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance reviewed by expert panel P:1U:4

Conservation

PhyloP100: 9.04

Publications

3 publications found

Variant links:

Genes affected

MYH7 (HGNC:7577): (myosin heavy chain 7) Muscle myosin is a hexameric protein containing 2 heavy chain subunits, 2 alkali light chain subunits, and 2 regulatory light chain subunits. This gene encodes the beta (or slow) heavy chain subunit of cardiac myosin. It is expressed predominantly in normal human ventricle. It is also expressed in skeletal muscle tissues rich in slow-twitch type I muscle fibers. Changes in the relative abundance of this protein and the alpha (or fast) heavy subunit of cardiac myosin correlate with the contractile velocity of cardiac muscle. Its expression is also altered during thyroid hormone depletion and hemodynamic overloading. Mutations in this gene are associated with familial hypertrophic cardiomyopathy, myosin storage myopathy, dilated cardiomyopathy, and Laing distal myopathy. [provided by RefSeq, May 2022]

MYH7 Gene-Disease associations (from GenCC):

dilated cardiomyopathy
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
dilated cardiomyopathy 1S
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
hypertrophic cardiomyopathy
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
hypertrophic cardiomyopathy 1
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
MYH7-related skeletal myopathy
Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
myopathy, myosin storage, autosomal recessive
Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
myopathy, myosin storage, autosomal dominant
Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
congenital myopathy 7A, myosin storage, autosomal dominant
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
Ebstein anomaly
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
familial isolated dilated cardiomyopathy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
hyaline body myopathy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
left ventricular noncompaction
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
arrhythmogenic right ventricular cardiomyopathy
Inheritance: AD Classification: LIMITED Submitted by: ClinGen
congenital heart disease
Inheritance: AD Classification: LIMITED Submitted by: ClinGen

MYH7 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2

For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000257.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYH7	NM_000257.4	MANE Select	c.1477_1478delAT	p.Met493ValfsTer19	frameshift	Exon 15 of 40	NP_000248.2
	MYH7	NM_001407004.1		c.1477_1478delAT	p.Met493ValfsTer19	frameshift	Exon 14 of 39	NP_001393933.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
MYH7	ENST00000355349.4	TSL:1 MANE Select	c.1477_1478delAT	p.Met493ValfsTer19	frameshift	Exon 15 of 40	ENSP00000347507.3
MYH7	ENST00000713768.1		c.1477_1478delAT	p.Met493ValfsTer19	frameshift	Exon 15 of 41	ENSP00000519070.1
MYH7	ENST00000713769.1		c.1477_1478delAT	p.Met493ValfsTer19	frameshift	Exon 14 of 39	ENSP00000519071.1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152158

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

Data not reliable, filtered out with message: AS_VQSR

AF:

0.00000410

AC:

AN:

1461886

Hom.:

AF XY:

0.00000550

AC XY:

AN XY:

727244

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.0000383

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.0000116

AC:

AN:

86256

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00000360

AC:

AN:

1112008

Other (OTH)

AF:

0.00

AC:

AN:

60394

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.467

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152158

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74326

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41434

American (AMR)

AF:

0.00

AC:

AN:

15266

Ashkenazi Jewish (ASJ)

AF:

0.000288

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5198

South Asian (SAS)

AF:

0.00

AC:

AN:

4822

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10614

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68032

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.525

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1Uncertain:4

Revision: reviewed by expert panel

LINK: link

Submissions by phenotype

Cardiomyopathy

Uncertain:2

Nov 30, 2021

ClinGen Cardiomyopathy Variant Curation Expert Panel

Significance:Uncertain significance

Review Status:reviewed by expert panel

Collection Method:curation

The NM_000257.3(MYH7):c.1477_1478delAT (p.Met493Valfs) variant has been identified in 1 individual with features of both HCM and DCM (Zimmerman 2010 PMID:20474083; Walsh 2017 PMID: 27532257, LMM pers. comm.) however, this is insufficient to apply the PS4 criterion. This variant was absent from large population studies (PM2; http:// gnomad.broadinstitute.org, v.2.1.1). This variant is predicted to cause a frameshift leading to a truncated or absent protein. The contribution of loss of function (LOF) variants in MYH7 to autosomal dominant inherited cardiomyopathy is incompletely understood therefore PVS1 was not applied. In summary, due to insufficient evidence, this variant meets criteria to be classified as uncertain significance for cardiomyopathy in an autosomal dominant manner. MYH7-specific ACMG/AMP criteria applied (Kelly 2018 PMID:29300372): PM2.

May 12, 2023

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Primary dilated cardiomyopathy

Pathogenic:1

Apr 26, 2016

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance:Likely pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

proposed classification - variant undergoing re-assessment, contact laboratory

not provided

Uncertain:1

Jan 08, 2025

Revvity Omics, Revvity

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Hypertrophic cardiomyopathy

Uncertain:1

Aug 07, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Met493Valfs*19) in the MYH7 gene. It is expected to result in an absent or disrupted protein product. However, the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in MYH7 cause disease. This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with clinical features of MYH7-related conditions (PMID: 20474083, 27532257). ClinVar contains an entry for this variant (Variation ID: 177817). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

PhyloP100

9.0

Mutation Taster

=0/200

disease causing (fs/PTC)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over